appendix

[uh-pen-diks]

noun

plural

appendices, appendixes 

1. supplementary material at the end of a book, article, document, or other text, usually of an explanatory, statistical, or bibliographic nature.

   Synonyms: supplement, addition, appurtenance, adjunct, addendum

2. an appendage.

3. Anatomy.

   1. a process or projection.

   2. the vermiform appendix.

4. Aeronautics.,  the short tube at the bottom of a balloon bag, by which the intake and release of buoyant gas is controlled.

appendix

/ əˈpɛndɪks /

noun

1. a body of separate additional material at the end of a book, magazine, etc, esp one that is documentary or explanatory

2. any part that is dependent or supplementary in nature or function; appendage

3. anatomy See vermiform appendix

appendix

plural

appendixes 

1. A tubular projection attached to the cecum of the large intestine and located on the lower right side of the abdomen.

2. Also called vermiform appendix

appendix

1. A small saclike organ located at the upper end of the large intestine. The appendix has no known function in present-day humans, but it may have played a role in the digestive system in humans of earlier times. The appendix is also called the vermiform appendix because of its wormlike (“vermiform”) shape.

Spelling Note

Appendices, a plural borrowed directly from Latin, is the usual plural, especially in scholarly writing, when referring to supplementary material at the end of a book. Appendixes is the usual plural in the anatomical meaning.

Word History and Origins

Origin of appendix¹

First recorded in 1535–45; from Latin: literally, “appendage,” equivalent to append(ere) “to add on” + -ix (equivalent to -ic- noun suffix + -s nominative singular ending); append

Word History and Origins

Origin of appendix¹

C16: from Latin: an appendage, from appendere to _append

Synonym Study

Appendix, supplement both mean material added at the end of a book. An appendix gives useful additional information, but even without it the rest of the book is complete: In the appendix are forty detailed charts. A supplement, bound in the book or published separately, is given for comparison, as an enhancement, to provide corrections, to present later information, and the like: A yearly supplement is issued.

Example Sentences

That is explained in an appendix more than halfway through the 394-page document.

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"By the time he got there, his appendix was completely burst, he had a blocked bowel, it was twisted. He was in a real mess," she said.

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Irwin wrote that after "13 years of fighting for answers" and two surgeries where she had 51 lesions, a cyst and her appendix removed, she was finally on the mend.

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The debate over Russiagate was reinvigorated last week when an appendix to another justice department investigation into the affair was declassified.

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For different levels of difficult behaviour the appendix to the guidelines suggests different staged interventions.

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Related Words

• addendum 
• postscript 

When To Use

Plural word for appendix

The plural form of appendix can be either appendices, pronounced [ uh-pen-duh-seez ], or appendixes, but appendices is more widely used. The plural forms of several other singular nouns that end in -ix or -ex are also formed in this way, such as index/indices, matrix/matrices, and codex/codices.  Irregular plurals that are formed like appendices derive directly from their original pluralization in Latin. However, the standard English plural -es is often also acceptable for these terms, as in indexes and matrixes.